Wandering Jew forms thick mats, particularly along creeks, mainly in the inner suburbs of Melbourne. Where there is Wandering Jew little else in the way of ground flora grows. It only takes one small fragment of leaf or stem and you end up with another plant.

You can count on the Backyard Blitz team to promote the next generation of Australian environmental weeds!

Popi

Tradescantia spathacea or Rhoeo is the one they have promoted.
Wandering Jew is Tradescantia flumensis.

Both are from tropical Central America.

How about you send an email to BY Blitz, and highlight your thoughts about this plant.

I agree with you it is a big concern, I have plenty of Tradescantia flumensis, at my place. We need to be vigilant about the availability of plants that could be potential weeds.

Up here in Queensland it is a vigorous growing plant that makes a superb ground cover. The large form does produce seed which can spread but the dwarf form shown on Backyard Blitz is sterile and can only be spread by division. If it happens to be put in an area where it shouldn't be believe me it is very easy to totally remove.

It is has extensively been grown in my area for many years and I have not once ever come across it in bushland areas. As I live adjacent to native bushland I will simply not grow anything that will easily escape and take over native areas. Just because it happens to be in the Tradescantia genus don't naturally assume that it is a weed species.

Andrew.

I would also remind you that just because a plant is sterile does not mean that it is safe for the environment. You need only look to Soursob for an example of this. Look at how pervasive that is around Melbourne despite the fact that it is sterile.

Have you ever seen Tradescantia spathacea growing wild around Melbournes bushland?? I think not. I lived in Cairns for many years and did not ever see it escape into bushland and it certainly hasn't done so here either. Yes other species of Tradescantia have weed potential and many are weeds in this area. It just appears to me that you don't like it because it is not a native. Well that is fair enough for you but you can't bag a plant because you simply don't like it! I use it and will continue to use it in landscapes that I design. If it were a weed here I wouldn't use it all. By the way I have been involved in tropical/subtropical bushland revegetation (including weed removal) for around 25 years so I know what is potentially a problem for the environment. I have more problems with the recently imported Pandanus utilis. Not for it's weed potential but for the potential of cross pollen flow with native Pandanus species in this area and thus creating hybrids or sterile plants.

With all due respect you are thinking short term and that is how we have created so many environmental problems for ourselves. I have no doubt that there are currently no infestations of Rhoeo in bushland around Melbourne or around Cairns.

But then that's probably what Australians thought about Soursob, Prickly Pear, Gorse, Boxthorn, Wandering Jew and Paterson's Curse 100 years ago. Now look at where we are with these plants - all were former ornamental/farm plants. You and I will almost certainly dead and buried by the time that Rhoeo becomes environmental problem.

What I am asking of landscapers like yourself is that you take a step back and look at the big picture. To consider legacy of environmental damage that you may be contributing to unleashing on furture generations.

Tradescantia flumensis is a major environmental weed from tropical central America. Tradescantia spathacea is also from tropical central America and is in the same genus because it has very similar charactersitics.

It does not take to much a a stretch of the imagination to conclude that the chances of it becoming a major environmental weed, like its 'sibling', are high.

There are plenty of Australian native or local native alternatives that will acheive the same effect if you care to exercise the grey matter and discover them. Why take such a large environmental risk when it is simply not necessary.

Let your fingers do the walking and do a Google search on the following string: "tradescantia spathacea" + weed. I think you will find Andrew, like I did, that tradescantia spathacea is a known environmental weed in Florida and many Pacific islands.

Try and learn from the mistakes of others Andrew. You will be doing our environment, our economy and our country a great service if you could just take a little time to research some of the exotic plant species you choose to use in your landscapes.

Unfortunately you obviously know little about this plant. There are many forms of it in cultivation. As I mentioned in an earlier post, yes the original 'large' form has weed potential and yes I know that it is a weed in Florida but the smaller 'sterile' form is not considered to be a weed in that area. I know that Tradescantia fluminensis is indeed a weed but comparing it to the dwarf form of tradescantia spathacea is like comparing a Queen (Cocos) Palm to a Coconut Palm.

You must too have some 'different' concepts and theories about plants. Why would the dwarf rhoeo all of a sudden become a weed when you and I are dead and gone??? It has been in cultivation here for many years now (around 15 years) and has shown no tendency to become a weed.

Most plants show their weed potential almost immediately such as wandering jew, prickly pear, asparagus fern etc (don't know those other things you mentioned obviously cold climate weeds)

And for your information YES I do research very thoroughly all exotic and native plants I use (a large number of natives are also unsuitable for this area because of their weed potential)

I also have a native only tropical rainforest area within my garden that does occasionally receive weeds mainly from birds droppings. Among these are exotics and some introduced natives from other areas of Australia

Finally, there is no native groundcover that 'does the job' that the dwarf form of Tradescantia spathacea does. They either don't perform as well, don't look as good or don't provide the desired effect. I do use other ground covers but for tropical gardens most others are too patchy, no colour or too hard to control.

You and I will just have to agree to disagree when it comes to this subject. I do have over thirty years of gardening and horticultural experience as well as the advantage of having a substantial knowledge of tropical plants and tropical gardening.

I have spent a number of years in bush crews trying to control exotic and Australian native weeds in remnant patches of native vegetation around the suburbs of Melbourne. So I think I can rightfully claim a better working knowledge of how weeds are spread than yourself.

For starters, I can think of a few native alternatives that create a similar effect, and are known to be non-invasive, off the top of my head. Dianella, Lomandra, Patersonia, Orhtosanthus and Stylidium.

With the exception of Orthrosanthus, these are local native plants around Melbourne so there will be dozens of other local native plants from other areas that I myself don't know about. Have you checked out your local indigenous nursery to see what else is available, including local but different forms of the above species.

I will also just remind you that Soursob is sterile so I have learned, at least in the Melbourne region. Despite this it is still an extremely aggressive environmental weed as I am sure you are aware. Soursob produces asexual 'seeds' that are spread widely by earth moving. The broken up rhizomes of Rhoeo can easily be spread in the same way and it will take more than 15 years for them to be sufficiently dispersed. So again you can't assume it is safe just because it is sterile nor that 15 years is sufficient to decide whether or not it is a threat.

And if Rhoeo was to suddenly and unexpectedly show signs of becoming invasive are you and other landscapers willing to go through all your landscapes and replace it or foot the bill for erradicating it from outside your garden beds?

I really think that what is necessary for people like yourself to see the light is for you to spend 6 months of so in a bushcrew as part of your horticultural/landscape training.

Perhaps if you spent 6 months scrambling over rocky escarpments etc with a 10L pack of herbicide on your back, for 8 hours a day in stinking heat or pouring rain, for $16 per hour, trying in desperately to prevent the tide of environmental weeds from smothering the last remnants of our local flora you might develop a little sympathy with the cause of people like myself.

Like the issue of smoking, our cause is growing slowly but surely and increasingly gaining traction with governments due to the considerable economic costs that environmental weeds (existing, emerging and future) exact. The restrictions on the horticultural and landscape industries are growing.

If you have been there and done that with environmental weed control, I cannot for the life of me understand why you would risk using using exotic plants of that nature. The 'cultural cringe' over Australian plants must be difficult to shake.

For mine, the big difference between the majority of GWebbers and a large proportion of the general public is that we spend enough time in our gardens to notice little things like one species taking over the entire backyard. If that sounds a little obvious, I can take you to a few Rocky backyards which have Orange Flame Vine and bougainvillea romping across neighbouring fences and sheds, with (seemingly) no complaint from anyone. Our fellow gardeners arent the problem - its the 'non-gardeners' out there who frustrate me.

Cheers,

Artie

Guys its no good telling us WE know all these things.

You are teaching in the wrong place

And I can see why we are loosing so many Members

And if you Greg want to debate about it this way go to Conversation and do it

As I am sick of all the bickering on these Forums...MM

What is this "cultural cringe" bit???

If you took the time to read the posts I have put up you will notice that I DO use native plants, have a native rainforest section in my own garden and yes I have used native ground covers such as Dianella & Lomandra. The simple fact is there is NO native ground cover that looks or does the job of Tradescantia spathacea. I use it and will continue to use it and I won't be dictated to by anyone with exotic homophobia. End of story!

BTW I am not a professional landscaper. I do designs and plantings for people because I am asked to and generally I don't get paid for doing it.

Come on guys. Even my flame wars aren't as vitriolic as this! Greg, you're going to have to learn that if you are too different from the people you are trying to educate, they simply won't listen to you. And they may have good reasons for disagreeing with your premises.

I'm still waiting to hear a good rational reason why we should make an effort to remove weeds from the bush - particularly bushland that people can't see. If a lantana grows in the woods, and nobody can see it, does it matter?

Why bother saving Tasmanian Devils from possible extinction due to the oral tumour disease?
Why bother trying to prevent the Nips from hunting minke, and now hump back, whales into extinction?
Why bother trying to prevent global warming?
Why bother trying to save the Wollemi Pine?
Why bother trying to protect Kakadu when most Australians will never see it?
Why bother trying to stop the Cane Toad?

Like all these ones, bushland weeds are an environmental issue that should get equal billing. All or nothing Nathan, all or nothing.

I will also point out that I am by no means th most radical proponent on this weed issue. There are those who regard indigenous plants from a different provenance as environmental weeds. I draw the line there because I recognize that it will be a cultural impossibility to get everyone to purchase only indigenous plants from their precise provenance.

The 'greenies' were regarded as ignorant hippies in the early days of the Green Movement. Now the Green Movement is becoming mainstream. I predict that the same will be the case with the environmental weed movement.

But there has to be people prepared to make enough noise and attract enough attention to get the issue on the societies' agenda, despite making some enemies along the way. No doubt many of these 'enemies' will find themselves on the outer sooner or later as have farmers who still refuse to stop clearing their land.

I use Griffin Microlaena for my lawns despite the fact that the provenance of this is in NSW some where. I accept the fact that most people want a grass that produces a lawn of equal quality to the familiar exotic species. Griffin Microlaena does this where as local varieties of Microlaena will not.

I figure that, if it escapes into bushland, at least it is still Microlaena and wont fundamentally alter the ecosystem. As is the case when non-seeding Kikuyu escapes and replaces seeding Microlaena. The survival of birds etc, that rely on Microlaena, are not going to be dependant on whether the Microlaena is 'Griffin' or local.

But recently I got the comment that I might as well just use Kikuyu or Rye Grass as use 'Griffin' Microlaena. So, as I said, I am by no means the most radical proponent of avoiding exotic plants.

I can sense your frustration as I also work in the business of managing the decline of the natural environment. I sense there is a general feeling in this forum that proponents of local provenance protection are not only disagreed with but are discouraged from presenting their view. I agree that members are being lost from the forum but I suspect that they are the purists.

It would make things easier if we could accept that a plant is only native to its provenance. It explains why we have native plants from one area of Australia that are invasive weeds in others. Just because Eastern Australia is connected to Western Australia by land mass doesn't mean that a plant native to the continent is appropriate anywhere outside it its area of genetic provenance.

Greg, I think it is hard for people to accept that they are doing anything wrong by planting exotics or non provenance natives. Trees of any sort are a good thing right? It is also hard for people to accept that the introduction of an invasive exotic into a remnant plant community results in loss of biodiversity. More is better Right? Unfortunately ecological systems are not linear, relatively small changes affect everything in that system and often in a disasterous way. Take nutrient runoff from gardens into bushland. I know as I suspect you do that it is impossible to restore bushland once it is degraded. Most Bushcare programs are bullsh*t, being nothing more than feelgood programs for people who spend 2 hours a month restoring the natural environment and then trashing it for the remainder. I work on plenty of bushcare sites which look great - very few weeds in sight - but are genetically dead because they cannot self sustain without people intervention. The older I get the more I lean towards protection rather than restoration.

I am interested in Nathan's question about why we should protect the natural environment. I occasionally have to defend my work as a bush regenerator (why?) from neighbours and members of the public. My reasons are that man does not have the god given right to totally dictate the nature of the total environment. Plant and animal species have rights to life as well. If a Bilby or Wollemi Pine could speak I'm sure they would have plenty of reasons to want to survive. I don't like using the argument that native plants may hold undiscovered cures or uses because this only reinforces the belief that the only reason for saving something is that
it may be economically useful to man. Survival of the fittest is a dangerous argument that can be used to justify almost anything including genocide.

Be encouraged by the realisation that peoples attitude towards the natural environment only moves in one direction, from indifference to fanatiscism and never the other way around. Keep giving them heaps Greg.

Formica

Why do you propose an arbitrary species of grass from elsewhere? Isn't it all or nothing? Personally the idea of a lawn gives me the quibbles. What a waste of valuable land.

I have moved away from the 'indigenous at all costs' philosophy and towards the permaculture ideas of efficiency and future proofing.

As a result, I enjoy growing native plants, because I like a challenge, because I feel a sense of patriotism to my home land, because some are beautiful or fascinating, because if I don't, who will? But I don't believe that rampaging against a marketing machine for the landscaping industry (backyard blitz, e.g.) is going to have any impact. Better to talk to Don Burke. And you'll find he has already thought about these issues and has come to what I feel is a far more supportable position.

Formica's point about restoration is exactly the same conclusion I've come to: I few weeks ago I said to Lynne that really bushland restoration is a complete waste of time , you may as well grow whatever plants you can. Why? Because unlike the small patch of remenant bushland near here, reveg tends to result in one age stands with very little or no self regeneration.

Is my ponit of view illogical? I don't know. I feel comfortable in my position having pondered these issues for many years, but I am very willing to change my world view if someone can find compelling evidence (something which apparently makes me autistic or something).

Nathan, despite our cities and technology humans are irrevocably dependant on the global ecosystem for our survival. All the issues I listed act in unison to errode biodiversity.

As the global ecosystem is like a brick wall, we would be foolish indeed to ignore the fact that bricks are being progressively removed from that wall.

One way or another all these seemingly unrelated environmental issues (to the ill-educated) will come back to bite us on the arse if we don't succeed in stopping them from happening.

As I said all or nothing. Although there is room for some compromises as with 'Griffin' Microlaena, among others.

koeksoetie is right. You need to understand your audience or you will just piss them off.

see this is the problem greg, people who come to this forum are not "native only" converts, people who come here are interested in natives, that's why theyre here, so some of us may only be 'half converts' like me, but when you start jumping on people for growing exotics it's like us 'half converts' dont belong here, we're not worthy to be in this forum, and heaven help any newbie who stumbles across this forum to ask a simple question, theyd probably run a mile in case they get jumped on for slipping up and mentioning they grow any exotics in their garden.

I think topics like this are important, and the last topic you started on the exotics vs natives issue was a really interesting thread with lots of views and opinions, but if youre too hard line people wont listen.

to be honest if there werent others like me here who grow natives and exotics happily together in their gardens, I would feel so alienated I wouldnt read this forum anymore, and perhaps my interest or focus on increasing the number of natives in my garden might wane a little too, which I think is the opposite of what you really want to achieve.

If this was a forum for native fanatics only, there'd be about 3 people here all agreeing with each other, and wouldnt that be a boring forum? lol

TG

Get the forum back on track and talk about what it was designed for - "Australian Natives".

We've got a good arena here for discussion on our favourite pass time - The good old "Aussie Native" - Don't throw it away.

* deciduous trees - I actually have got N. gunnii growing in tubes, but it is far to picky to survive as a shade tree. The northern species are too unpredictable for use as shade trees.

* fruit and veg - I am good friends with one of australia's top indigenous food experts, and she agrees that very few natives are good cultivation foods.

* grapes - nothing comes close to grapes for providing fruit , shade and autumn colour.

* hardiness - when you look at council plantings they try to use natives, but it is often the gazanias, diosma and SA flags that really thrive in mid road plantings.

* bonsai - I've been doing native bonsais for 10 years now, and still I struggle to get compelling forms. The best ones I've seen have been on the large end of what constitutes bonsai because natives just don't seem to look right miniature.

* bamboos - bamboo is a wonder material, and having a local supply of it is very useful for building. I've got some large culm sympodial bamboo for building material, and I know of no native with similar harvesting properties (the closest is probably swamp paperbark!).

I am not simply jumping on people for growing exotic plants as I myself grow a few of them, i.e. culinary herbs and veges. Nor am I opposed to people growing their Camelias, Roses, Gardenias or any other exotic plants that have no established track record of being environmental weeds else where in the world. There is room for compromises but not at the expense of the greater environmental good.

What enrages me is people in a position to know better, i.e. landscapers and horticulturalists, who continue to distribute known or potential environmental weeds through ignorance or indifference. And for such a trivial reason as 'garden fashion'.

Our collective position on exotic plants has to be considerably more cautious and suspicious of any new exotic plant introductions. We already have a flood of exotic environmental weeds that is eating away at the Australian environment like a cancer.

It does not make sense to add to it by continuing to import exotic plants without subjecting them rigorous testing. Or by continuing to distribute existing exotic plants that are discovered to have a track record of weediness else where or that are showing signs of invasivness here.

I do not regard myself as a 'purist' either. If someone purchases a Dianella revoluta in Ballarat and plants it in Epping then I do not consider it an environmental weed. I would see it as a vast improvement on Tradescantia spathacea. I always encourage people to stick as closely as possible to local provenance however.

I think we need to piss a few people off about this issue. The people who are pissed off are normally the main offenders. The early greenies pissed plenty of people off with their environmental protestes and still do. Yet society is becoming more and more 'green' with each passing year.

As with all these issue there is a greater good at stake over which personal preference should not be allowed to take precedence.

You seek your advice from else where lorraine_b, I am quite prepared to loose friends on this!

Sorry mate for saying this but you need to get a life!!!

All of the ranting and raving in the world is not going to convince me or anyone else here to 'totally' convert to native.

I do very much like to use natives where I can but quite often they don't do the job or give the right effect.

I DO consider the environment and I DON'T use anything that has been 'proven' to an environmental weed.

Your climate and your environmental conditions are vastly different to what is experienced here. I know what are the problem plants for this area and even the local environmental groups don't consider the dwarf non seeding form of Rhoeo to be a problem.

What a boring world it would be if every garden in the street used only local provenence natives! It is a persons right to have a personal choice about their garden styles and the plants they grow. It is up to us to respect that right.

As a huge fan of tropical gardens, I sometimes find myself looking at articles and thinking 'Great - another collection of palms, cordylines and crotons ...'. At its most mundane, the 'carbon copy' approach can create any number of tropical gardens which appear the same, but there will always be gardeners who will rise above the pack and create something outstanding. I particularly enjoy seeing something unexpected in a garden and thinking 'Why didnt I think of that ?'.

At the risk of repeating myself, the problem isnt the plants, its us. I obviously dont adhere to Greg's teachings, but I dont dismiss local provenance purely because it might be too boring. One of the more frustrating aspects of my ongoing search for local rainforest natives is that so few people propagate them anymore. Grevillea Venusta aside, many of these species seem to be locked away in our national parks : its almost as though our government doesnt want gardeners to grow them.

Happy Trails,

Artie

Although I must confess a certain satisfaction in provoking a reaction from members of the opposing camp, you are basically irrelevant in the grand scheme of things.

My primary target is more reasonable minded people who might be persuaded of the merits of our argument and who might eventually apply enough pressure (legislation, covenants, etc) to enforce a change in attitudes.

Reasonable \Rea"son*a*ble\ (r[=e]"z'n*[.a]*b'l), a. [OE.
resonable, F. raisonnable, fr. L. rationabilis. See (Reason),
n.]
1. Having the faculty of reason; endued with reason;
rational; as, a reasonable being.

If anyone is being unreasonable here it is you. So far your entire philosophy seems grounded on wishful thinking. I know, because I believed much the same thing too once. Then I spent some time learning about way our world works, and I've come to the realisation that it very deluded.

Gardening Australia last night covered the issue rather well - John Patrick and Clive Blazey talking about food gardens mentioned that we should move away from gardens full of ornamentals and towards gardens of edibles. That's where I'm headed, and I'm hoping some of you might too.

Btw, Kunzea 'badja carpet' makes a nice rosemary like herb. Goes well with lamb (might be worth doing a toxicity test though!).

His message is clear and reasonable and something vital that affects us all. (OK so the important sentiments are at times expressed in a pointed manner and a little less personal attacks would be greatly appreciated by many). In the next few decades we will all be faced with huge changes in our environment that could change civilisation as we know it. Environmental ecosystems play a massive part in the balance of our societies on earth and the rich lifestyle that we have. We all know this and should take time a little more often to think objectively. Unfortunatley it is too easy to not ever think about it as humanity's cleverness and success has ironically provided us with a lifestyle that has allowed us to quite happily live in our own extremely comfortable bubbles.

It's far too easy to think that it means nothing to us if a species of plant, or animal becomes extinct at our hand, as they don't come into our everyday lives. We do know that small changes can have many effects down the line of food chains, weather patterns, rainfalls etc. We know this.

We should rejoice in the resources that we have, ie technology, science, history and know that if applied well we can fix and prevent (as well as create)these problems.

I feel that Greg is just another passionate person trying to point this out, not throw opionions of aesthetics or choice or personal attacks.

Yes interesting that program last night Nathan, I also do that plant the veggies in the garden beds with day lilies and petunia one year I had tomato bushes growing longside my newly planted bougainvillea where ever I find room the veg go in, not as neat and pretty as that one but does that matter...

I understand the thought, I just don't see it as practical in the world as it is. I also am not sure what the point is (something that greg has not yet addressed). What is the benefit of replacing all our existing infrastructure? As it stands, none of the native foods produce enough to meet demand without increasing energy or land costs. The general consensus is that the specific example of weed choice originally cited is not an issue.

We have have systems in place to control weeds, and it seems that the biggest sources of weeds are people who just plant something cheap they picked up from a friend and just stick plants in any old way. Not the sort to watch backyard blitz and even less the sort to be swayed by arguments.

Furthermore, it seems that real weed problems are no longer fed by garden escapees, but rather by self-sustaining populations of reverted forms.

Greg's claim that the specific species in question will suddenly change into a rampaging environment killer has so far not been evident, and yes, it could turn into a killer, but so could lechenaultia biloba (something greg advocates) - see also Pittosporum undulatum. Furthermore, I am less and less convinced that garden escapes alone are the problem, but rather the change in soil that occurs around cities as we pump vast quantities of various chemicals into the ground.

Perhaps we should consider cities as they are, rather than how the land was 100 years ago. Restoring bush land might cost $1million /acre. Is it better to encourage people to contain their mess?

It is quite plausible that most of the weed problems are symptoms, not the disease itself. Removing the weeds might just cause erosion and habitat loss for animals. More significantly, why is it important to preserve biodiversity?

Many species have died out in the life of Earth. Why do we care about a plant that cannot cope with change, particularly when we live in a time of great genetic upheaval.

An alternative view point about preservation of life is to consider the goal of life being to maximise utilisation of space. In this view point weeds can be a blessing or a curse depending on the long term effects of their introduction. This viewpoint differs most obviously from the conservation viewpoint when it comes to issues such as colonising other planets - a 'conservative' would despise such an attempt, a 'pangean' would welcome it.

Finally, Greg weakens his case dramatically after making a big deal about a no-compromise position on indigenous plants to then go and say that D. revoluta from ballarat is fine in Epping. What is a valid line to draw in this situation? 1km? 10km? 10000km? Why? I argue that planting a non-local species of indigenous plant is more harmful than planting a non-invasive exotic due to the potential for diversity loss.

I think everyone should get a pony.

There are three likely outcomes to me saying this:

1. people dismiss my remarks as not relevant or 'rude' or something (essentially avoiding the question), or live in cognitive dissonance.
2. people find a valid weakness in my argument (in which case I will happily change my tune)
3. people will find my argument compelling and come to agree with me.

Either 2) or 3) are useful for everyone present, but sadly 1) is the most common and simple makes everyone angry.

You can lobby whoever you like to have exotic plants banned but you will basically get nowhere. You certainly will not EVER affect myself or what I do in my garden.

I just feel sorry for your neighbours, heaven help them if they decide to plant a petunia or two!!! When you display this sort of attitude to them possibly the result would be you copping a smack in the mouth!

"What we are doing now to biodiversity is like burning Renaissance masterpieces to cook dinner." Professor E. O. Wilson, Scientist and writer

"BIODIVERSITY is the web of life –the thin skin of living things, including us, which inhabits the surface of planet Earth. Biodiversity includes humans, animals, plants, fungi and microbes - from dugongs to daisies, toadstools to termites. This variety of life has evolved over hundreds of millions of years. We don’t know how many species live on Earth – scientists have described about 1.8 million. But it is estimated that there are 10 to 100 million which probably exist.

Yet what has taken millions of years to evolve is now being destroyed at a breathtaking rate. Professor Harry Recher, Edith Cowan University, estimated we could be losing eight species an hour, or 70,000 a year world-wide. That’s a faster rate of extinction than at any time since the dinosaurs died out 65 million years ago. Yet plants and animals today are not dying out because of a maverick meteorite. Rather, it is the actions of our own species, clearing natural habitats, spreading pest plants and animals, and dumping pollutants into the rivers, oceans and atmosphere. A group of independent Australian experts recently identified biodiversity loss as "perhaps the most serious environmental problem in Australia today" and "a cause for national concern". They said species in all major groups of plants and animals are at risk (Australia: State of the Environment 1996).

Since European settlement in Australia, 10 out of 144 species of marsupials have become extinct with unknown numbers of invertebrates and lower order creatures. We have lost three species of emu - the King Island, Kangaroo Island and mainland Tasmanian emus are all extinct. Today, more than 100 mammal species are endangered, vulnerable or potentially vulnerable. Forty per cent of Australia’s forests are gone, including 75 per cent of our rainforests, leaving many forest ecosystems also endangered. Biodiversity is our living heritage, providing us with food, clothing, housing, clean air and water, inspiration and spiritual renewal. It’s an integral part of our lives, and it’s easy to see that protecting biodiversity today will pay off for the future health of human society, our economy and all life on earth.
Yet how can we benefit from it without destroying it? "

I agree with some of what has been said in this debate but I lament the lack of maturity and diplomacy. When an arguement gets personal, points might be scored but the arguement isn't advanced. I am concerned that those who read these posts without participating are not being well served.

As for hippies, I have always wondered just how 'environmentally sensitive' you can be with a clapped-out Kombi. I admire the fact that several of you donate your weekends to LandCare, but people like Peter Garrett and Bob Brown realise that the Big End of Town isnt going to change their ways for the sake of a few trees. Much easier to throw a few million at re-vegeation and PR spin doctors.

We can all see the problems inherent in big corporations continuing to pillage the land, but its a long way from the pulpit to salvation, Brother Greg.

But perhaps if enough of us pause in our daily wallowing in the mud, and lift our eyes towards the tree tops, we might manage to effect a further raising of the evironmental standards. And perhaps postone for a little longer the inevitable collapse (at least as we currently know it) of human civilisation.

Thank you for your contribution. My own view comes from the direction of your post, and had you not posted that, I probably would have had to post a similar if simpler and more humble response.

I happen to believe that our Australian flora has its own innate value, and that losing species diversity is a sad effect of human actions locally and globally.

Some years ago when chaos theory/fractal maths was the topic of conversation, it was illustrated by saying that the effect of the movement of butterfly wings in one part of the planet could induce a massive change in weather patterns in another part. Whether that was an exaggeration or not, it was meant to say that we could induce massive changes from a very simple seemingly-innocent action.

The problem with humanity has been that it has acted a little like the proverbial bull in a china shop. We are only now starting to realise the effects of our actions. The South Australians are probably aware that after settlers first moved northwards in their state to graze animals, it was not long before they discovered that their actions were unsustainable and led to desertification, so that the land was destroyed and people then had to abandon that area or treat it in a much less impactful manner. Salinity from forest clearing in WA is another example.

My own fear, based on the butterfly wings analogy, is that our climate could change massively in a very short time. People recently modelled the effect of the greenhouse effect on accelerating the greenhouse effect - they now expect as much as a 6 degree average temperature increase over a matter of decades. I wonder whether there are some so far ignored variables not modelled, which could dramatically worsen that.

I guess that maybe I am going off on tangents, but I also suspect that plant species could die off massively from climate change alone. That would also greatly affect fauna. And all these things are interlinked. Even humanity could suffer terribly from this process.

I suspect that we have very little understanding of all the ecological and environmental interactions, because they are potentially so complex. I believe that we should try to have the least possible effect on our environment as possible, for fear of ultimately totally destroying it and in the process destroying ourselves.

So if we introduced an exotic plant that subsequently became a weed, we could end up massively changing the environment to everyone's harm. Therefore I agree with Greg - I would prefer us to very carefully check each proposed new plant introduction. The CSIRO has done that in trying to overcome the problems of past imprudent introductions such as rabbits. These plants could have an effect equivalent to that of rabbits. And even the CSIRO has got it wrong on occasions - such as when the cane toad was introduced.

If you have read this post, you will note words like "believe", "suspect" "fear", "guess", "could", and those are value-laden for good reason. It will not satisfy people like Nathan, who wants concrete facts and hard reasons to change his view. Unfortunately, I don't believe we have the luxury of waiting until the Earth is degraded or even destroyed and we have concluded that we should not have done what we did, before we act to minimise our impact on it.

Regards,
Frank

REMBEMER I AM CRAZY!!!

(im just trying to also lighten the mood!)

Clearly the gardening 'establishment' would rather that I just shut up and let them go doing what they have always done.

However it is heartening to see that a small number of people on this forum also care about the issue enough to speak up. Rome wasn't built in day as they say.

The reason I want facts is because acting without the facts can compound the problem, such as introducing the cane toad in the belief that it would solve the cane beetle problem. Without understanding we will act like bulls in a china shop. Think about it a bit, please!

It seems to me that Greg, Andrew, myself and many of the others all agree that biodiversity is of great importance and weeds are a danger to the environment. If that is so, then surely many of our hearts are basically in a similar place.

But what we do to protect biodiversty is the issue that certainly raises the blood pressure! Greg I appreciate your concerns and your commitment but I believe more folk than you realise, would agree with you if you were not so belligerent and intolerant of ideas that are not all that far from your own.

I have been in the landscape industry since the 1970's and since then, the issues of biodiversity, introduced weeds, bush regeneration and native gardens have come a long long way. These issues have made enormous progress and continue to do so. This progress has been made by patient, steady quiet work by lots of inspirational people.

I would like to say a lot more but the previous lines of discussion do not encourage me. It is just too dominated by cheap point scoring and disparaging remarks.

What you are perhaps refering to is introduction of exotic insects and diseases to control existing environmental weeds.

Robert NSW, some one has to be prepared to be labelled as belligerent and intollerant in order to move forward with a particular issue. Damning of the Franklin River, for example, was not halted by many people working quietly behind the scenes. It was halted as a result of very loud and visible 'cat fight'.

I am also sure that most people on this forum have their heart in the right place when it comes the environment. None the less I still believe that many are simply not seeing or refusing to see the connection between many exotic plant species and damage to the environment.

Currently I get the feeling that you actually have no idea why you believe what you do, and are thus becoming more and more shrill in your efforts to convince others (perhaps as a way of compensating for your own unease).

I will now restate my position: Cities are already a damaged environment; we cannot realistically restore the original biosystem (due to extinct pollenators, fungi, changed soil chemistry, etc); we are currently destroying larger and larger areas of bushland to provide resources (food, materials, energy) for our cities (worldwide); this damage could be reversed if we used the city environment properly (Paris was an exporter of food in the 19th century); the way to use the city properly is to use the vast human capital to provide high intensity crops close to home. People have demonstrated sustainably providing a person's worth of food in 50m^2 in suburbia, to produce the same amount in the country (with lower soils, less labour, less 'waste fertilisers' etc) might take 500m^2 per person. It has been estimated that more agricultural money and resources are used to maintain lawns in the US than goes into food production.

By all means find flaws in my argument, that way I can grow. But just waffling and making various appeals to 'good nature', 'higher authority' or ad hominem attacks is a waste of everyone's time, and critising others without having done your homework is very counterproductive.

However I am extremely reluctant to use them because all Grevilleas cross pollinate freely. And using them in close proximity to populations of indigenous Grevilleas will result in a lot of 'mongrel' Grevilleas in the environment.

I even find it hard to see how that may reduce biodiversity - at first site it looks as though you will increase biodiversity. But you don't tinker with an extremely complex machine unless you know exactly what you are doing.

I might be presuaded to use them deep in the inner suburbs where cross pollination with wild Grevilleas is not going to happen. But I certainly would not use them in places like Eltham and St Andrews.

This might seem like a copout, but I really have to ask if *anything* we do in Oz is going to make a difference. I know we should think globally and act locally, and I also know that we export a lot of the coal being burnt in power stations across the globe, but seeing cities like Hong Kong, Singapore, Jakarta and Bangkok up close really sits you on your backside. Watching countless tuk-tuk/bemo/minibuses idling in congested streets, pushing countless hydrocarbons into the atmosphere day after day, makes even SYD/MEL/BNE look meagre by comparison.

- Motor vehicles are also a status symbol in Asian cities : middle-class Bangkok mothers wouldnt be seen dead putting their little darlings on a *bus* each morning. This is a town where gridlock can happen at 1am, and said mums have to be on the road by 5am to get their kids to school on time.

- GM is banking on growth in China to arrest multi-million dollar losses in its other operations

- a very large part of the demand for Australian resources comes from the boom in China : its all a house of cards, but my Super is riding on that house.

Again, we can pontificate from our ivory towers, but these people are so busy just trying to 'catch up' that the environmental impact is largely forgotten. Australia and NZ can definitely work harder to preserve our relatively 'clean' environments, but we dont live in a bubble. Jakarta and Surabaya are both closer to my house than Perth and Adelaide, but I cant tell the people of Indonesia that they need to start 'waking up to themselves'.

Maybe its time to move to that log cabin on the West Coast of Tassie after all.

Cheers,

Artie

Similarly, we need to reduce our water consumption, our fertilizer consumption, our farming footprint, etc. My global footprint is 3.7 hectares currently, compared to an average in Melbourne of 7.6. If the rest of the world were raised to my standard of living we'd need two Earths.
http://www.earthday.net/footprint/index.asp
Of that, 2.1 hectares are food related, and I already have a careful diet (more vegis than most people, eat local produce etc); so I could possibly reduce my footprint by a half by growing my own food, making real conservation possible.

Considering that transportation is more than half our oil demand, and that food transport is a rather large chunk of the transport pie, reducing food transport by city agriculture seems a worthwhile response.

I started my indigenous landscaping business in order to give me leverage on this environmental weed issue. I did not grab at the environmental weed issue to provide leverage for my business.

When I first started getting concerned about environmental weeds I soon relized that a computer programmer was never going to be taken seriously on it by the general public. So I found myself with two options:

1) Become a wage earner for Greening Australia or DPI or DSE etc
2) Or start a specialised business and use it to highlight the issue.

As I have never been comfortable with the restraints imposed on you as a member of a large organisation, I chose the latter option.

then we could say our current practises are working and we could tell people like Greg to pull their heads in. Clearly the state of our natural environment is not improving so something has to change. Some landscapers, garden designers and nurseries continue to be irresponsible in their use of plants - I wonder how long Liriope will take to appear in the bush. What Greg is saying needs to be said. I know there are many other factors contributing to the problem but lets start with this aspect.

Arti - your comment on the hippies driving the Combi shows your predjudice and ignorance rather than any great insight. Leaving aside the stereotype issue, would you be happier if the "hippies" dumped the Combi and bought the latest 4wd every two years. Although the emissions of a Combi may be higher, think of the overall emissions produced from the manufacture of a new 4wd. The so called hippies I know leave a very light foot print on the earth unlike my clean living, church on sunday neighbours.

This really is an important debate. If nothing else it is forcing people to think and argue their position. To those who threaten to leave the forum because it is too confronting then BooHoo. No-one suffers more the slings and arrows than the pro-indig environmentalist, for us the stuff here is pretty tame.

Formica

As Greg is pushing for indigenous gardens, he should be willing to put forward why he belives that to be true, in logical point form. Particularly if he is trained as a computer programer!

Greg, to get you going, here's a start:

We believe that indigenous only gardens are the best way to confront environmental damage because:
a) the plants are especially suited to our climate and thus need little care.

You need to write the other 26 points. Then I will comment on some and you will correct your statements. repeat.

I agree in principle that if you want to grow ornamentals, then indig is a reasonable first choice, but I then say, fine, but there are many other ornamentals, many of which provide something that indig species don't. Why is that unreasonable?

Alright for Nathan's benefit and for that of any other readers who can't see a link between environmental weeds and environmental degradation here are some specific examples. They are are based on my own observations on the weed control job as well as accepted teachings within Conservation & Land Management courses.

I am not going to site scientific papers providing proof, that Nathan would no doubt demand. If readers wish to do that then be my guest and I am sure they will find a plethora of papers that provide evidence of direct links between environmental weeds and environmental degradation.

1) If you include the farming behaviour of humans as being a ligitimate mechanism for dispersal of environmental weeds then you might look at wheat farms as massive infestations of an environmental weed, with negligible biodiversity. What happens in drought:
a) The farm turns into a dust bowl.
b) The soil progressively blows way or washed away due to freak high rainfall events.
c) With greatly reduced top soil the farm is no longer able to sustain cropping while regeneration of native vegetation is unlikely due to loss of native plant seeds in the lost top soils.

What else happens:
a) The shallow roots of the wheat crop intercept very little run-off.
b) Increased amounts of water reach the water table causing it to rise.
c) Salt is brought to the surface destroying crops and preventing regeneration of native vegetation.

None of this would happen if there was a diversity of native shrubs. Despite drought enough species would survive to prevent soil blowing away. Deep rooted trees and shrubs would intercept run-off thus preventing the water table to rise.

2) Wandering Jew forms dense mats that prevent just about all other plant species from gaining a toe hold, so you pretty end up with something that resembles a wheat farm. Wandering Jew is none the less shallow rooted and some times large swathes of it can be peeled away by high flow events leading to exposed creek banks. As there are little other ground cover species or shrubs in place massive bank erosion can ensue in the event of subsequent high flow. events. This would not happen if there was a diversity of native species. Some would no doubt be washed away however enough would withstand the high flow events to prevent the worst of the erosion. Some large trees may fall into the water way and act as a damn, slowing water flow and preventing severe erosion. Large shrubs and grasses growing on the lower banks would similarly act as a buffers of various grades between the flowing water and the banks.

3) This is an example from the country of Wales that was presented in an ABC tv program with David Attenborough(can't remember the name of it). Rhodendrons are a particular problem in Wales. They form huge infestations that acidify the soil to a considerable extent. Even if they are cleared nothing else can grow, except for more Rhodendrons. So the land become completely unproductive or humans and animals alike.

4) African Boxthorn forms huge infestations around Melbourne. Where there are Boxthorns you normally find rabbits and rabbits strip way ground cover vegetation. So you often find rabbit warrens and severe errosion among the boxthorns. The boxthorns also make farming land unproductive due to the high cost of removing them and controlling re-growth.

I could keep going but that should be enough give people the picture.

All of your examples are why we shouldn't have a monoculture, but that is not your original claim. I can simply suggest that we grow multicrops with lots of different species (say an apple and orange orchard interplanted with taro, spinach, rosemary, pansies and warragul greens). You haven't addressed why the plants should be indigenous.

(Probably 'private life of plants')

I want to see a logical argument, not made form specific examples, but going from premise to conclusion. A medical scientist should have no trouble with this! A set of examples can always be countered with an alternative set of examples: A Mangrove swamp is a monoculture of mangroves, yet they form an essential plant community (do you suggest we replace them?).

There in lies the problem of continuing to introduce exotic plants and animals - who can possibly anticipate interactions like this, i.e. beyween a European mammal and an African shrub? And this a good reason to er on the side of caution.

There is a lot more to a mangrove swamp than what you usually see on the television by the way. A mangrove swamp is not a monoculure at all (The Living Planet - David Attenborough). If memory serves me correctly there are several species of mangrove alone that form a mangrove swamp community. One species dominates the intertidal zone (not including aquatic vegetation), other species dominate the above high water mark and still other species form trees further inland.

If there are any existing monocultures it is no doubt due to the fact the above high water mark components have been cleared for development or farms.

And I am afraid I can't offer you any examples of environmental weeds in mangrove swamps because it they are outside my experience and teachings at NMIT. Have have no doubt the scientific literature will yield some examples of environmental weeds that have destroyed mangrove swamp ecosystems (some where in the world), as evidenced by plumetting populations of particular coastal fish species dependant on them for breeding.

Nathan, these sorts of examples are broadly accepted and acted on by environmental scientists, governments, CSIRO, government land managers, Greening Australia, conservation organisations and now many farmers. You can't seriously be suggesting that they are all be acting on flawed logic and false assumptions!

Nathan I reckon that no matter what evidence or logic anyone puts in front of you it will not change your mind because it doesn't fit your own belief system.

Nathan, you're line of arguement is no better than Gregs.

There is an obvious philosophical line and/or point of view, that goes through Greg's posts. It may well be one that we disagree with, but it is clearly there. Nathan, consistant ridicule and condescension might satisfy your ego but it unfortunately inhibits constructive debate.

Whether the issue is the threat of exotic garden plants becoming weeds and therefore their resultant impact on biodiversity or whatever native plants we plant and where we plant them, bludgeoning someone who has not provided the right words for you, is unhelpful.

You own statements can be rather suspect. For example:

"I'm still waiting to hear a good rational reason why we should make an effort to remove weeds from the bush - particularly bushland that people can't see." - Surely that reason has been given more than clearly. Also a quick google will give you countless reasons.

"I few weeks ago I said to Lynne that really bushland restoration is a complete waste of time , you may as well grow whatever plants you can. Why? Because unlike the small patch of remenant bushland near here, reveg tends to result in one age stands with very little or no self regeneration." - Not true! You need to get around more. There are good examples in Melbourne that even this New South Welshman is aware of. Please don't get picky and ask me to name them all! The Merri Creek is one though and there are some excellent ones out Footscray way.

"Swamp paperbark (M. quadrangulata?) "has a known history as an environmental weed overseas." (It is actually Melaleuca quinquenervia and is an excellent example of an exotic weed wrecking enormous stretches of the Florida everglades)

"Restoring bush land might cost $1million /acre." Way, way, way off the mark! Join one of the growing number of bush regeneration groups and you will understand.

"we don't have a good formal argument as to why indigenous is important." - This really is a perverse statement! For goodness sake read all the stuff about biodiversity etc. Check out the Australian Department of the Environment web pages; there are lots of books written about this subject.
Haven't you heard of a bloke called Tim Flannery?

"I don't need scientific papers, merely a logical argument." - Speak for yourself.

Goverments have a good record of doing things for reasons other than logic. I am constantly amazed how people do the wrong things for all the right reasons. Just the other day in my work I discovered that the 'right way' to solve a certain computer algorithm was slower than another way known about for even longer. After a certain point behaviour becomes entrenched and self-catalysing even when it is known to be wrong.

Nathan I reckon that no matter what evidence or logic anyone puts in front of you it will not change your mind because it doesn't fit your own belief system.

Au contrair, I am far more likely to change my belief system than you. As I said, I used to believe what you believe, but then I began to doubt the fundamental assumptions.

I notice that you still haven't managed to write an argument. Is it too hard?

Robert wrote:
There is an obvious philosophical line and/or point of view, that goes through Greg's posts. It may well be one that we disagree with, but it is clearly there.

There was an obvious philosophical line etc from Stalin. It is possible to be convinced about one's beliefs and yet be wrong. It is also possible to write scientific papers, and be wrong. Sometimes people even retract their statements, but this seems to be very much in a minority.

Nathan, consistant ridicule and condescension might satisfy your ego but it unfortunately inhibits constructive debate.

Actually, as far as I can tell, I've been trying to have constructive debate, but it's hard to debate when the counterviewpointholders don't even know what they're arguing for. I've tried asking indirectly, I've tried asking nicely, I've tried giving hints and even suggesting methods and started writing greg's argument for him. But he refuses to actually state his cause. How can one have a constructive debate when one isn't sure what the other person's reasoning is, and when at the same time, one feels that that person's actions are illogical and harmful?

Whether the issue is the threat of exotic garden plants becoming weeds and therefore their resultant impact on biodiversity or whatever native plants we plant and where we plant them, bludgeoning someone who has not provided the right words for you, is unhelpful.

You mean saying things like 'in the big picture you are irrelevant' and 'Clearly there are people in this forum who are not 'converted''? I'm just asking for a simple sketch of why greg believes that we should grow indigenous only gardens with base beliefs, middle deductions and final conclusion. There is no 'right words' about it.

Lets say I were a medical scientist, and I started going around on TV saying that we should stop parents from giving immunisation injections. How would you react? Would you a) ask me to state my reasons careful, b) respect my position and let me continue or c) write lengthy letters to critics telling them to be nice to me, who is obviously doing it for the right reasons?

What if you knew someone who's child had died from polio?

"I'm still waiting to hear a good rational reason why we should make an effort to remove weeds from the bush - particularly bushland that people can't see." - Surely that reason has been given more than clearly. Also a quick google will give you countless reasons.

But not in a single carefully explained point of view. That's what I'm asking for, and who better to write it than a medical scientist who is trying to push for indigenous only gardens?

"I few weeks ago I said to Lynne that really bushland restoration is a complete waste of time , you may as well grow whatever plants you can. Why? Because unlike the small patch of remenant bushland near here, reveg tends to result in one age stands with very little or no self regeneration." - Not true! You need to get around more. There are good examples in Melbourne that even this New South Welshman is aware of. Please don't get picky and ask me to name them all! The Merri Creek is one though and there are some excellent ones out Footscray way.

I've been involved in attempts to restore endangered species back into their wild habitats. They never work. Once you've lost the pollenators or the fungi or whatever you can never put it back.

"Swamp paperbark (M. quadrangulata?) "has a known history as an environmental weed overseas." (It is actually Melaleuca quinquenervia and is an excellent example of an exotic weed wrecking enormous stretches of the Florida everglades)

Your point?

"Restoring bush land might cost $1million /acre." Way, way, way off the mark! Join one of the growing number of bush regeneration groups and you will understand.

I've had that figure quoted by numerous people - biologists working at Monash, landcare nursery growers, an indig nursery owner in tassie, a famous caravan park owner in WA etc. They all seem to think that if anything, $1m is an underestimate.

Sure, you can put some nice trees and whatnot in, but that's not the same as restoring the bush. The only method I know of that works is to slowly migrate existing bushland out using things like the bradley method, and this is very labour and time intensive and requires a patch of existing bushland. Nothing like what Greg is proposing.

"we don't have a good formal argument as to why indigenous is important." - This really is a perverse statement! For goodness sake read all the stuff about biodiversity etc. Check out the Australian Department of the Environment web pages; there are lots of books written about this subject.

I haven't found any that say that growing indigenous gardens is anyway helpful. Many bemoan our 'cultural cringe', but I haven't read any serious books that propose that solving environmental weeds should start by growing indigenous only gardens.

Haven't you heard of a bloke called Tim Flannery?

I know Tim. I think he'd be a better person to discuss this with...

"I don't need scientific papers, merely a logical argument." - Speak for yourself.

Scientific papers are a form of appeal to authority, and allow the debater to avoid thinking.
Logical arguments can be brought down to a set of beliefs which can be tested alone. Furthermore, with a logical argument it is possible to see alternative solutions, something that appeal to authority can't provide.

I'll wait until something of substance has been added to the debate

OK I've done my research on cane toads, and you are right, they were "not introduced by CSIRO, but by the sugar industry":

http://www.austmus.gov.au/factsheets/canetoad.htm

"Cane Toads were introduced to Australia to eat French's Cane Beetle and the Greyback Cane Beetle. The 'whitegrub' larvae of these beetles eat the roots of sugar cane and kill or stunt the plants. The Australian Bureau of Sugar Experimental Stations imported about 100 toads from Hawaii to the Meringa Experimental Station near Cairns. The toads bred quickly and more than 3000 were released in the sugar cane plantations of north Queensland in July 1935."

Whoever introduced them is now irrelevant to the damage they have caused as a feral animal.

I also took note of the following extract from your latest post:

Nathan:"I few weeks ago I said to Lynne that really bushland restoration is a complete waste of time , you may as well grow whatever plants you can. Why? Because unlike the small patch of remenant bushland near here, reveg tends to result in one age stands with very little or no self regeneration."

Robert: "Not true! You need to get around more. There are good examples in Melbourne that even this New South Welshman is aware of. Please don't get picky and ask me to name them all! The Merri Creek is one though and there are some excellent ones out Footscray way."

Nathan: "I've been involved in attempts to restore endangered species back into their wild habitats. They never work. Once you've lost the pollenators or the fungi or whatever you can never put it back."

That last statement of yours says it all for me. I am interested in outcomes - in minimising the effects we have as per the bull in a china shop analogy. . The above quote has demonstrated why we should be extremely careful about introducing exotic plants (and animals). It shows that doing so has multiple complex effects on an ecosystem. That's all I need to know.

Yes, I agree that acting without facts can compound a problem, such as introducing the cane toad in the belief that it would solve the cane beetle problem. The point was that the cane toad was an introduced species, and it upset the natural balance.

But how can we compound a problem that does not exist? We would not have a problem to compound had we left the natural order as it was i.e., not imported exotic plants (or the cane toad).

So I have taken your advice and thought about it some more. My conclusion remains the same: exotic plants are a potential danger to our environment and need to be very carefully checked before we allow them to be imported.

Quarantine and trialing are a most important part of australia's protection network (Ask Steve Irwin!).

As a general principle, it is best to try to maintain pristine areas, and fully utilise degraded areas.

Now keep following that thought and see where you end up.

With his pesimistic view of bushland regeneration I think that Nathan is forgetting that the field cannot not be much more than 20 years old. We have a long way to go, much research still to do and many more techniques or combinations of techniques to try before we give it up as a lost cause.

Perhaps one day, probably beyond our lifetimes, some one will discover the environmental keys to reversing the damage. Is it therefore morally acceptable to let much of the Australian landscape turn to $hit just because we can't see a way to solve the problem now?

What about genetically engineered viruses that target particular environmental weed species? Perhaps nanotechnology could also play a role here one day.

Hawaii is one place I'd love to visit, but I'll be careful not to mention my admiration for Australian plants to any of the locals. They might give me a surfboard and a tow to the Outer Reefs on one of the 30-foot plus days ...

"My own fear, based on the butterfly wings analogy, is that our climate could change massively in a very short time."

Today an ABC on-line news story (link below) said in part:

"Research has found sediment drilled from the floor beneath the Arctic Ocean holds prehistoric climate records that show Arctic temperatures reached subtropical levels about 55 million years ago.

"The cylindrical sediment core provides new data showing that long ago the surface water was a warm 18 degrees Celsius and then Arctic temperatures reached 23 degrees Celsius.

"The mean annual Arctic temperature today is around minus 20 degrees Celsius.

"Today's models under-predict how warm the poles were back then, which tells you something disturbing - that the models, if anything, aren't sensitive enough to greenhouse gases," said Matthew Huber of Purdue University in the United States."